Senior Research Fellow Wins Major International Science Award

April 10, 2008

Senior Research Fellow Arthur J. Nozik of the U.S. Department of Energy’s National Renewable Energy Laboratory has won the 2008 Eni Award, a prestigious international honor that has several Nobel Prize winners among its recipients.

Nozik received the award in the science and technology category. It honors his revolutionary work leading a large NREL team that is exploring future generation concepts for solar conversion. His team discovered and verified multiple exciton generation (MEG) in semiconductor nanocrystals, also called quantum dots, and recently found efficient MEG in silicon quantum dots. He shares the award with Stefan W. Glunz of the Fraunhofer Institute in Germany.

Nozik will receive his Eni Award at a May 20 ceremony in Rome. It will be presented by Italian PresidentGiorgio Napolitano.

“What we are trying to do is to turn MEG into the reality of a much more efficient solar cell. This will spur us on,” Nozik said of the award.

The ultimate goal is to make the cost of solar power equivalent to the cost of coal so that countries, particularly developing ones, will be able and motivated to use clean and carbon-free solar power rather than fossil fuels.

MEG produces more than one electron–hole pair from a single absorbed photon, potentially resulting in more efficient conversion of sunlight into electricity. When today's photovoltaic solar cells absorb a photon of sunlight, about 50 percent of it is lost as heat. MEG provides a way to convert some of that energy lost as heat into additional electricity.

Until Nozik’s work leading the NREL team, the generation of multiple electron-hole pairs per absorbed photon was only found to occur in semiconductor materials that aren’t presently used in commercial solar cells and frequently contain environmentally harmful materials such as lead, or they are in a range of photon energies not useful for solar cells. Finding MEG in silicon is significant because it is a raw material abundant in the Earth’s crust and has no harmful environmental effects.

Nozik’s work also demonstrates that MEG occurs in the visible region of the solar spectrum rather than just with ultraviolet light, meaning more of the solar spectrum could be used to produce electricity.

The 2008 Eni Award is a new award that is the successor to the previous Italgas Award, which was created nearly 20 years ago by Italy’s largest energy company to promote and reward the frontier of scientific research and innovative applications in sustainable energy.

NREL is the U.S. Department of Energy's primary national laboratory for renewable energy and energy efficiency research and development. NREL is operated for DOE by Midwest Research Institute and Battelle. The work honored by the Eni Award was supported the U.S. DOE Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences.